Method and device for producing an edge

ABSTRACT

The present invention relates to a method and a device for folding a foil material half-shell edge which protrudes from a surface of the packaging of a packaged food product, said half-shells receiving the food product. The half-shells have flanges, at least some regions of which lie one on top of the other and which form the protruding edge. The aim of the invention is to improve a quick and reliable method which can be carried out with little effort for improving the appearance of food products packaged in foil half-shells. This is achieved in that during a relative movement between a packaged food product and a die, an edge region of the die presses against the protruding edge of the foils, whereby the edge of the foils is at least partly folded to lie substantially flush on one of the half-shells. The invention further relates to a device which corresponds to the method.

The present invention relates to a method and a device for folding afoil material half-shell edge which protrudes from a surface of thepackaging of a packaged food product to lie substantially flush havingthe features of the preambles of the independent claims.

EP 2 765 081 A1 describes a generic process for manufacturing packagesfor food products and a device for carrying out said process. These foodproducts may be hollow chocolate figurines which may be shaped, forexample, into chocolate eggs, chocolate Santa Clauses or chocolateEaster bunnies. Here, first two packaging half-shells of a ductilematerial, preferably aluminium foil or a foil of another metallicmaterial, are shaped each with one protruding flange face between whichthe food product will be received in a subsequent process step so thatthe protruding flange faces are lying one on top of the other flatly.The inner surfaces of the half-shells and the flange faces lying one ontop of the other are laminated with a meltable material, preferablypolyethylene. Then, the flange faces are sealed to each other using heatand pressure. In a subsequent procedure step, the protruding flanges arecut to size, and a distal flange section is bent over by about 90° sothat in the subsequent procedure step the bent over section of theflanges may be crimped over onto a non-bent section. Upon completion ofthis procedure, the thus sealed and bordered edge of the flanges lyingone on top of the other protrudes from the surface of the food productand affects the aesthetic appearance of the packaged food product.

WO 93/01093 also describes a process for packaging food products intofoils. In a corresponding tool, foil half-shells in which the foodproduct is received are initially shaped. The half-shells haveconnection flanges lying one on top of the other which are subsequentlysealed to each other and form an edge protruding upright from thesurface. A subsequent folding of the so-called Saturn ring to liesubstantially flush is mentioned as optional in WO 93/01093.

DE 1 260 949 describes a method of manufacturing figurines of candy massenveloped in thin metal foils. In the process, a bordered connectionbetween two preformed foil half-shells having protruding edges isformed. The edges are first placed one on top of the other, subsequentlyfolded upwards into one direction, and finally folded over an inner edgeface. A radially protruding edge with an increased stiffness remains.

It is an object of the present invention to suggest a method accordingto the above type by which the appearance of food packaged in foil-likehalf-shells can be improved, and which may be carried out reliably,quickly and with little efforts. Furthermore, a generic device which issuited for carrying out the method is to be provided.

According to the invention, this object is achieved by a method havingthe features of claim 1.

During the relative movement between the die and the food product, acontact between the edge region of the opening of the die and theprotruding foil edge occurs whereby the foil edge is deformed and willthus bend over in the direction of the movement of the food product sothat it at least partially abuts against the surface of at least one ofthe half-shells.

The edge region of the opening of the die may have a closed or aninterrupted contour. By such interruptions, the protruding edge does notcome into contact with the entire circumference of the edge region sothat only a partial folding is allowed. The opening of the die mayfurthermore consist of one or several parts. If these parts are spacedapart in the circumferential direction, the interruptions of the edgeregion may be formed between them.

By the low number of procedure steps, the method may be carried out inquick succession and with a constant packaging quality for successivepackaged food products and is therefore suited for time-efficient seriesproduction. Furthermore, by the process control which can be designed tobe simple and which essentially relates to the control of the relativemovement, an automation of the process can be advantageously realized.

By this folding of the initially protruding edge to lie substantiallyflush, the position and the presence of the parting plane of thehalf-shells is less obvious. The surface of the packaged food productthus appears altogether smoother, whereby the contour of the productwill better show to advantage. Thereby, the appearance of the packagedproduct will be improved.

According to a variation of the invention, at least one elastic elementmay press onto the protruding edge at the edge region of the die,whereby the edge of the foils may be at least partially folded to liesubstantially flush against at least one half-shell. The clearancebetween the elastic element and the packaging surface may be selectedsmall enough for the elastic element to graze over the packaging surfaceand to fold the edge to lie substantially flush at the outer contour ofthe packaged food product. The elastic element may deform during thecontact with the protruding edge by the occurring compressive forces andthus better follow the shape of the packaged food product to increasethe folding quality. By its deformation, the elastic element causesspring forces onto the edge that act opposite to the direction ofdeformation. After the contact with the edge and the elastic deformationof the elastic element caused thereby it will resume its original shape.

At the edge region of the die, bristles may possibly press onto theprotruding edge, whereby the edge of the foils may be at least partiallyfolded to lie substantially flush at a half-shell. During the contact,the bristles may be elastically deformed and graze over the packagingsurface, whereby the protruding edge may be better folded to liesubstantially flush at complicated and uneven contours of the packagingsurface. By the elastic deformation, the bristles cause a spring forceon the edge opposite to the direction of deformation. After the contactwith the edge, the bristles resume their original shape.

In a preferred embodiment of the invention, the die may be at rest andthe packaged food product may be moved through the opening relative tothe die. This permits a resting mounting of the die through the openingof which the product may be moved target-orientated with an accurate fitand with a relatively simple guidance. This provides a high quality ofthe folded edge.

In an alternative preferred embodiment, the packaged food product may beat rest and the die may be moved relative to the packaged food product.If the product is held at rest, the die may be moved easily, though withan accurate fit, relative thereto, and this results in a high quality ofthe folded edge.

Advantageously, both the packaged food product and the die may be moved.This results in a greater freedom of the design of the method and thepaths covered by the elements involved. Depending on the shape of theproduct, relative movements may be caused thereby by which the edge maybe better folded to lie substantially flush to certain contact sectionsof the product.

According to a development of the invention, the edge of the foils maybe initially approached, in a first step, during the passage through theopening of the die, to the surface of the half-shells, and subsequently,in a further step, folded to lie substantially flush at at least onehalf-shell. Before the final folding to lie substantially flush at thesurface of the half-shells, the edge may be initially preformed in acontrolled manner, for example to approach the shape of the edge to befolded to lie substantially flush to the outer contour of thehalf-shells. In some packages and materials, it showed to be moreadvantageous for an appropriate folding of the edge to select astep-wise process for folding by which the deformation behaviour of theedge is better taken into consideration.

Preferably, the relative movement between the die and the packaging mayextend one-dimensionally. This type of movement facilitates the processcontrol and reduces the procedure steps necessary for folding the edgeto lie substantially flush and the overall time for carrying out theprocess.

Favourably, the relative movement of the packaged food product may firstextend in a first moving direction through the opening of the die, andsubsequently transverse to the first moving direction to adapt thefolding of the edge to lie substantially flush at the outer shape of thefood product. A relative movement consisting of several movementcomponents in various directions permits greater freedom in the foldingof the edge, above all to complex outer contours of the surface of thehalf-shells. Thus, during a first partial movement in a first direction,the edge may be tangentially folded to lie substantially flush at a partof the surface to then be adapted to the outer contour of the half-shellby means of one or several relative movements of the die.

In a preferred embodiment of the invention, the packaged food productmay be moved by means of guide means relative to the die. By the guidemeans, the direction and speed of the relative movement may becontrolled. The guide means may optionally be designed in the form of amale mould.

In a particularly preferred embodiment, the packaged food product may beheld at the guide means during the relative movement. Thus, the packagedfood product may be securely positioned during the folding of the edge.

In a further, particularly preferred embodiment, the packaged foodproduct may be held at the guide means by means of a vacuum. Thispermits a secure and product-protecting fixing of the food product tothe guide means while the fixing is easily releasable.

Advantageously, the packaged food product may be held between the guidemeans and a backing part. The guide means and the backing part may be incontact with the packaged food product at various sides to adjust andcontrol its position. By the additional backing part, an improvedfixability of the packaged food product may be achieved.

Particularly advantageously, the backing part may exert a guiding forceonto the packaged food product. This may be optionally done by means ofa resilient element. By the guiding force, which may act in thedirection of the relative movement of the packaged food product, asecure positioning of the packaged food product and a control of themoving direction may be ensured during the operation.

In a particular manner, at least a part of the guiding force between theguide means and the backing part may be transmitted over the packagedfood product. Optionally, the whole guiding force may be transmittedbetween the guide means and the backing part over the packaged foodproduct. Thus, the process may be altogether simplified because theproduct itself serves as a force-transmitting component. Surprisingly,this may also be applied when hollow chocolate figurines are packagedwhich are sufficiently stable to also transmit the guiding forces.

Optionally, the guide part and the backing part may be spaced apart sothat it is ensured that the folding of the edge is not obstructed bythese parts. The foil edge may be located between the spaced apart partswhile the packaged food product is positioned between the guide part andthe retention part. Thus, during the folding process, it will only comeinto contact with the edge region of the die and possibly a pre-bendingelement. Thus, a high fitting quality may be ensured.

According to a further development of the invention, the protruding edgemay have a proximal section which is directly connected to thehalf-shells and connects a distal section of the edge with thehalf-shells, wherein the distal section is folded onto the proximalsection before the edge is folded to lie substantially flush. Thesection of the edge which is initially further apart from the surface ofthe food product is being bent over so that it is in flat contact withthe section of the edge which is closer to the food product. By thistype of pre-packaging, the edge may be bordered, whereby a borderedflange is formed and a reliable mechanical closure of the food productin the region of the edge may be ensured.

According to a particularly advantageous further development of theinvention, the distal section may be directed with its front end towardsthe direction of the surface of at least one half-shell before foldingand in particular touch it or be spaced apart from it. Thereby, thefolded joint or the bordered joint of the edge will better remain in theclosed position during folding.

Possibly, the packaging may move through the opening of the die with theproximal section leading so that the proximal section may come intocontact with the edge region of the opening, and the distal section maybe at least partially folded to lie substantially flush at at least onehalf-shell. By a relative movement designed in this way, the distalfolded or bordered section is quasi folded to lie substantially flush ata half-shell of the product whereby the security of the bordered orfolded joint is improved both with the edge folded and during thefolding of the edge to lie substantially flush.

Advantageously, the flanges may be bordered, sealed to each other, orbordered and sealed to each other before the edge is folded. These typesof connection permit a mechanically secure connection of the flanges.

In a particularly advantageous manner, the packaged food product maycompletely cross the die. On the one hand, this provides a good foldingof the edge which in any case passes through the die, on the other handit permits the possibility of further transporting the product on thisside after it has been passed through the die.

The object according to the invention is furthermore achieved by adevice according to claim 18.

The device permits a quick and reliable folding of the edge to liesubstantially flush with a simple process control and an uncomplicateddesign. The contour of the edge region of the die opening follows theouter contour of the packaged food product at those points or regionswhere the protruding edge is to be folded so that the edge may come intocontact with the edge region. Thereby, the edge region is able toplastically deform the protruding edge during the contact so that it atleast partially fits to at least one of the half-shells.

The device permits a quick and easily controllable folding of theprotruding edge to lie substantially flush. It may process a high numberof packaged food products in series within a short time and with aconstant packaging quality.

By the contact with the edge region of the opening during the relativemovement, the position of the protruding edge with respect to the foilhalf-shells is modified so that it may at least partially be folded tolie substantially flush at at least one of the half-shells. Thereby, theappearance of the packaged product is improved.

The opening may have a closed or an interrupted contour. Suchinterruptions may be designed so that the edge does not come intocontact with the edge region where the opening is interrupted and isneither folded there. The edge region may furthermore consist of one orseveral parts. The parts may be spaced apart so that the interruptionsof the opening are created between them.

In one embodiment of the invention, the edge region of the die may haveat least one elastic element which presses onto the protruding edge. Theelastic element may deform during the contact with the edge region andthe packaged food product so that the protruding edge may be betterfolded to lie substantially flush at complex and non-uniform outercontours of the packaged food product. The deformation of the elasticelement is elastic, that means that the elastic element will resume itsoriginal shape after the contact with the edge. During the deformationof the elastic element and its contact with the protruding edge, springforces are acting on the edge.

According to another embodiment, the edge region of the die may havebristles which press onto the protruding edge. The bristles may beelastic to graze over the surface of the packaged food product and foldthe protruding edge to lie substantially flush at the surface of thepackaged food product so that it better follows its outer contour. Afterthe elastic deformation by the contact with the edge, the bristlesresume their original shapes. By the elastic deformation of thebristles, they cause spring forces that act on the edge.

In one variation of the invention, the clearance between the edge of thedie bordering the opening and the half-shells may be, at least in someregions, smaller than the width of the protruding edge. The width of theprotruding edge is the distance between the packaging surface of thehalf-shells and the end of the protruding edge remote from the surfaceof the half-shells. With a clearance between the edge of the diebordering the opening and the half-shells that is at least in someregions smaller than the width of the protruding edge, the edge regionof the opening of the die may be brought into contact with theprotruding edge to fold the protruding edge to lie substantially flushat the half-shells.

Advantageously, the distance between the edge of the die bordering theopening and the half-shells may at least in some regions correspond tothe thickness of the protruding edge. The thickness of the protrudingedge extends transverse to its length protruding upwards from theproduct and corresponds to the overall thickness of the foil layerswhich form the protruding edge. By such a design of the distance, a goodapproach of the edge to the surface of the half-shells is permitted.

In particular, the guide means may comprise retention means for thepackaged food product. By means of these retention means, the packagedfood product may be held at the guide means. Thus, a secure positioningof the packaged food product is possible.

In one possible embodiment of the invention, one or more suctionelements may be provided as retention means. By means of the suctionelements, a vacuum may be created which exerts a retention force ontothe surface of the packaged food product and thus holds the latter. Thesuction elements permit a reliable, careful and easily controllablereleasable connection between the retention means and the packaged foodproduct.

Optionally, a backing part opposite the guide means may be provided bywhich the packaged food product may be held between the guide means andthe backing part. Thereby, the packaged food product may be securelyfixed between the guide means and the backing part and is guided in itsmovement through the opening of the die.

According to a further development of the invention, the backing partmay exert a compressive force onto the packaged food product which isdirected opposite to the direction of the relative movement of the foodproduct through the opening of the die. This compressive force improvesthe fixability of the food product during the relative movement.

In a particularly advantageous manner, the backing part may comprisespring means which may exert a compressive force onto the packaged foodproduct. Such spring means are an advantageous possibility of exerting acontrollable compressive force with little constructive efforts.

Advantageously, the device may furthermore comprise a pre-bendingelement for approaching the edge to the surface with an opening whoseedge region is further spaced apart from the half-shells than thethickness of the flanges lying one on top of the other in some regions.Depending on the constructive design of the packaging and the product,and of the material, a better folding may be achieved thereby ifinitially, a pre-bending is effected before a further folding to ahalf-shell of the product is accomplished.

In one embodiment of the invention, the die is fixed and the guide meansare movable. Thereby, a resting mounting of the die is permitted. Theproduct may be moved through the opening of the die with an accurate fitand targetedly with a relatively simple guidance. This provides a highquality of the folded edge.

In a further embodiment, the guide means are fixed and the die ismovable. When the food product is at rest, the die may be moved relativeto the food product easily and with an accurate fit. This results in ahigh quality of the folded edge.

According to a development of the invention, the die and the guide meansare movable. Thereby, a greater freedom in the design and control of themethod and the paths covered by the elements involved is achieved.Depending on the shape of the product, relative movements are therebypossible, by which the edge may be better folded to lie substantiallyflush at certain contact sections of the product.

Possibly, the die and the guide means may be movable in one singledirection relative with respect to each other. This facilitates thecontrol of the folding process.

In a particularly advantageous manner, the die and the guide means maybe movable in several directions relative with respect to each other.This facilitates a folding of the edge to lie substantially flush evenat complex external shapes of a packaged food product.

In a particularly advantageous manner, the edge region of the opening ofthe pre-bending element tapers towards the edge region of the opening ofthe die. By the tapering, the reduction of the distance between thehalf-shells and the respective edge regions is realized so that in theregion of the greater distance, the pre-bending can be realized, and inthe region of the die with the small distance, the edge may be closerfolded to lie substantially flush at the surface of the half-shells.

Favourably, the pre-bending element may be embodied as a chamfer of theedge region of the opening. During the pre-bending process, theprotruding edge will slide over the chamfer and will be bent towards thesurface of the half-shell in the process.

According to a development of the invention, the flanges that at leastpartially lie one on top of the other are bordered to each other, sealedto each other, or bordered and sealed to each other. These types ofconnection improve the closure of the flange connection.

In an advantageous embodiment, the guide means and the backing part maybe spaced apart. In this distance, the edge to be folded may be locatedso that it may be folded without contacting the backing part and theguide means, thereby increasing the fitting quality.

Several embodiments of the invention are represented in the drawingsdescribed below.

In the drawings:

FIG. 1a shows a vertical section through a food product packaged in foilhalf-shells and a die and guide means before an edge is folded to liesubstantially flush according to a first embodiment of the invention,

FIG. 1b shows a vertical section through the packaged food product ofFIG. 1a after the edge has been folded to lie substantially flush,

FIG. 2 shows a vertical section through a packaged food product withflanges sealed to each other before and after the edge is/has beenfolded to lie substantially flush according to a second embodiment ofthe invention,

FIG. 3 shows a vertical section through a packaged food product withflanges bordered to each other before and after the edge is/has beenfolded to lie substantially flush according to a third embodiment of theinvention,

FIG. 4 shows a vertical section through a packaged food product withflanges bordered and sealed to each other before and after the edgeis/has been folded to lie substantially flush according to a fourthembodiment of the invention,

FIG. 5 shows a vertical section through a fifth embodiment of a deviceaccording to the invention for folding an edge to lie substantiallyflush having guide means, retention means, a die, a pre-bending element,a backing part, and a resilient element with a packaged food product,

FIG. 6a shows a vertical section through a detail of a food productdirectly before the contact with a die according to a sixth embodimentof the invention,

FIG. 6b shows a vertical section through the detail of the food productof FIG. 6a during folding in contact with the die,

FIG. 6c shows a vertical section through the detail of the food productof FIGS. 6a and 6b with a folded edge directly after the contact withthe die,

FIG. 7a shows a vertical section through the detail of a packaged foodproduct according to a seventh embodiment of the invention directlybefore the contact with a die having bristles,

FIG. 7b shows a vertical section through the detail of FIG. 7a duringthe contact of the edge with the bristles of the die while the edge isbeing folded to lie substantially flush,

FIG. 8a shows a vertical section through a detail of a packaged foodproduct according to an eighth embodiment of the invention directlybefore the contact with a die having an elastic element,

FIG. 8b shows a vertical section through the detail of FIG. 8a duringthe contact of the protruding edge with the elastic element while theedge is being folded to lie substantially flush.

The method according to the invention and the device according to theinvention relate to the packaging of food products. These food productsmay in particular be hollow chocolate figurines with any external shape,for example the external shape of eggs, stylized animals or humanfigurines.

Proportions in size and dimensions represented in the Figures are notdrawn to scale but are selected to represent the features of theinvention clearly. In general, the thickness of the foil is clearlysmaller than the thickness of the outer hull of a hollow food product.The combination of optional features of the invention is given by way ofexample and is not to be considered in a restricting manner.

FIG. 1a shows a first embodiment of a device according to the inventionfor folding an edge of a packaged food product to lie substantiallyflush in a schematic sectional view before the contact with the die. Thefood product has the outer shape of an egg. The joint face of the foilhalf-shells in which the flanges lie one on top of the other isperpendicular to the image plane. The direction of the relative movementof the packaged food product with respect to the die is designated bythe arrow R and lies in the image plane.

The packaged food product 1 is received in two foil-like half-shells 2,which comprise flanges 3 flatly lying one on top of the other. Theflanges together form a protruding edge 4, which may be brought intocontact with an edge region 8 of the die 5 during a relative movementwhose direction is represented by means of an arrow R. In the shownembodiment, the device moreover includes guide means 6 by means of whichthe relative movement may be performed. In this Figure, the guide meansare designed as movable male mould while the die is mounted at rest.

The external shape of the food product has the shape of an egg and isrotationally symmetric. The two foil half-shells have identical shapes,their contact plane lying in the plane of the largest cross-section ofthe packaged food product when they receive the food product betweenthem. Since the cross-section of the food product preferably tapers fromthis plane on, it may be better inserted in the foil half-shells duringthe packaging process. The foil-like half-shells are thereforeconfigured as half-shells in the shown embodiments. Instead of identicalhalf-shells, a packaging according to the invention may be also formedby mirrored half-shells or half-shells of different shapes.

The foil half-shells with the protruding flanges are preformed from foilsections cut to size, for example by means of deep-drawing. Thecurvature of the foil half-shell resulting from deep-drawing correspondsto the outer contour of the food product which is received and packagedin the half-shells.

As a packaging material, an aluminium foil may be employed which may beexternally provided with a print to create, in connection with the shapeof the food product, an attractive appearance of the packaged product.The foil may have a thickness of 5 to 100 μm, in particular 10 to 50 μm,and particularly advantageously 15 to 40 μm. However, the foil materialis not restricted to aluminium nor metallic materials.

The protruding edge 4 has a width B and a thickness D. Between the edgeof the die bordering the opening and the half-shells, there is aclearance A perpendicular to the relative movement. The shown arrow Rindicates the direction of the relative movement of the packaged foodproduct in relation to the die 5. Here, in the represented embodiment,the packaged food product is not necessarily moving. The relativemovement of the food product in the direction of the arrow may also berealized by a resting product and a moving die.

The clearance A is smaller than the width B of the protruding edge.During the passage of the die in the moving direction designated by thearrow R, the protruding edge comes into contact with the edge region ofthe die. In the process, the edge region exerts a compressive force ontothe protruding edge which is transmitted to the guide means via the foodproduct. By the compressive force, the protruding edge deformsplastically and is at least partially folded to lie substantially flushat one of the half-shells.

In the shown first embodiment, the opening of the die has a closedcontour without interruptions. Across the entire circumference of thepackaged food product, the protruding edge comes into contact with theedge region of the die and is deformed thereby. Equally, an open orinterrupted contour of the die opening is possible by which parts of theprotruding edge do not come into contact with the edge region.

During the folding of the foil edge to lie substantially flush,compressive forces may act on the food product due to the process. Toavoid damages, the forces may be adapted to the stability of the foodproduct, depending on the occurring forces and environmental influences,for example ambient temperature.

Below, the same reference numerals are assigned to the same elements inthe Figures.

FIG. 1b shows the packaged food product of FIG. 1a , however after theoriginally protruding edge has been folded to lie substantially flush.After the relative movement between the packaged food product and thedie and the contact between the edge region of the die and theprotruding edge caused during the contact, the formerly protruding foiledge is approximately tangentially folded to lie substantially flush atthe surface of the packaged food product.

FIGS. 2 to 4 show food products pre-packaged in half-shells of afoil-like material wherein the flanges of the half-shells lying one ontop of the other are connected to each other in different ways. Left ofthe parting line M drawn in perpendicularly, the protruding edge is ineach case shown before folding, and right of the parting line, the edgeis partially folded to lie substantially flush at the surface of one ofthe half-shells.

FIG. 2 shows a packaged food product before and after the edge has beenfolded to lie substantially flush according to a second embodiment ofthe invention, wherein the protruding edge is formed by two flanges ofthe half-shells lying one on top of the other and which are sealed toeach other at the sealing area 9. Sealing may be accomplished by meansof material-bond joining processes, such as gluing, fusing, soldering orwelding. To this end, the metal foils may be coated on the inner sidefacing the food product either completely or in sections with athermoplastic polymer, for example polypropylene or polyethylene, sothat the thermoplastic layers lying one on top of the other at theflanges will fuse due to heating and form the sealing as a resultthereof.

FIG. 3 shows a packaged food product before and after the folding of theedge to lie substantially flush according to a third embodiment of theinvention, wherein the flanges forming the edge are bordered to eachother. The front face of the bordered edge points in the direction ofthe upper half-shell and is spaced apart from it. During the borderingof the edge, the two flange faces initially lie one on top of the otherand form the protruding edge. Then, a distal section of the edge is bentover by about 180° so that it is placed onto the proximal section andpressed against it. The bordered edge is secured against a release ofthe connection. By the bordering of the edge, it has an increasedthickness which is approximately four times the foil layer. The distalsection of the edge points with its front face towards the upper foilhalf and is spaced apart from its surface.

FIG. 4 shows a packaged food product before and after the folding of theedge to lie substantially flush according to a fourth embodiment of theinvention, wherein the flanges of foil half-shells forming the edge areboth sealed and bordered to each other. As is also shown in FIG. 3, thedistal section of the edge is directed towards the upper foil half-shelland spaced apart from it. The thickness of the protruding edge isapproximately four times one foil layer.

FIG. 5 shows a fifth embodiment of the device for folding an edge of apackaged food product to lie substantially flush. Next to the packagedfood product 1, which is packaged in two half-shells 2 having flanges 3and forming a protruding edge 4, a die 5 with an edge region 8 definingan opening 7 is shown. Furthermore, the device has a pre-bending element12, which is designed as a chamfer 13 of the edge region 8 of theopening 7. The packaged food product is held between guide means 6 and abacking part 10. By means of a resilient element 17, the backing partexerts a compressive force onto the packaged food product. The guidemeans comprise retention means 11 designed in the form of suctionelements. The suction elements hold the packaged food product by meansof a vacuum created by a vacuum generator 18.

In this embodiment, there is no contact between the guide means 6 andthe backing part 10. The retention force exerted by the backing part 6onto the packaged food product 1 is completely transmitted via thepackaged food product 1 to the guide means 6. Thereby, neither the guidemeans nor the backing part come into contact with the protruding edge,whereby a non-obstructed folding of the edge to lie substantially flushat the surface of the half-shells may be ensured.

By the resilient element 17, a compressive force is exerted via thebacking part 10 onto the packaged food product and is forwarded via thefood product to the guide part 6 without permanently deforming ordamaging the food product. The resilient element may be designed, forexample, in the form of one or several coil springs, pneumatic orhydraulic springs or actuators or energy accumulators.

The retention means designed as suction elements of the guide meansoperated with a vacuum are also suited, apart from their function ofholding the packaged food product during the folding of the edge to liesubstantially flush, for gripping the packaged food product beforefolding, for example by a conveyor means or by a tool by which aprocedure step preceding the edge folding step has been performed.Similarly, the food product may also be placed again, after the edgefolding, onto a conveyor means or into a tool for subsequent proceduresteps.

When the packaged food product is passed in the direction of therepresented arrow R, the protruding edge initially comes into contactwith the pre-bending element 12, subsequently with the chamfer 13, andfinally with the edge region of the opening of the die. During thecontact with the pre-bending element and the chamfer, the protrudingedge is thus first deformed and continuously approached to the surfaceof the half-shells before it is folded to lie substantially flush at thesurface of the half-shells not before it passes the opening and contactsthe edge region.

The protruding edge has a proximal section 14 and a distal section 15.The proximal section 14 here connects the distal section 15 with thefoil half-shells 2. During the relative movement of the packaged foodproduct through the opening of the die 5, represented by the arrow R,the proximal section 14 comes into contact with the edge region 8 of thedie 5 so that the distal section of the edge is at least partiallyfolded to lie substantially flush at one of the half-shells.

FIGS. 6a to 6c each show a detail of the food product with the edge in asectional representation at different points in time during the foldingof the edge according to a sixth embodiment of the invention. Therepresented arrows R and E show the respective direction of themovements of the packaged food product relative to the position of thedie.

In FIG. 6a , the protruding edge is shown directly before the contactwith the pre-bending element 12. The die 5 has a pre-bending element 12,an edge region 8 and a chamfer 13 extending between the edge region 8and the pre-bending element 12. The clearance A between the edge regionof the die and the surface of the half-shell corresponds to thethickness D of the protruding edge. During the passage of the die, theprotruding edge is folded to lie substantially flush at the surface ofthe half-shell without being appreciably compressed in the direction ofits thickness. The direction of the relative movement of the packagedfood product is shown by arrow R.

In FIG. 6b , the already pre-bent edge is shown in contact with thechamfer. During the represented procedure step, the edge is pre-formedbefore the final folding. In the exemplified embodiment, the edgeslides, during the deformation, over the chamfer, whereby it iscontinuously bent in the direction of the surface of the half-shells.

In FIG. 6c , the folded edge is shown directly after the passage throughthe opening of the die. After the contact with the edge region 8 of thedie, the edge is folded to lie substantially flush at the surface of oneof the half-shells 2. In this position, the food product may be moved inthe direction shown by arrow E relative to the die, or the die may bemoved relative to the food product in the correspondingly oppositedirection so that the edge may be even better adapted to the outercontour of the packaged food product. This second movement does not haveto be perpendicular to the first one but may be in any directiontransverse to it. To improve the folding of the edge to its entirecircumference, this second movement may extend in several directions topress the edge against the surface of the packaged food product fromvarious directions. Apart from the two represented moving directions,both one single direction and any number of different directions andcomponents of movement are possible.

FIGS. 7a and 7b each show a detail of the packaged food product 1 with aprotruding edge 4 and a die 5 having bristles 19 according to a seventhembodiment of the invention. The relative movement of the packaged foodproduct 1 extends relative to the position of the die 5 and in thedirection of the arrow R.

The shown active principle corresponds to that in FIGS. 6a to 6c . Equalor corresponding elements of the invention are designated withcorresponding reference numerals.

FIG. 7a shows the die 5 and the food product 1 just before the contactof the bristles 19 with the surface of the packaged food product 1. Thedistance between the bristles 19 and the food product 1 is hereoptionally selected such that the bristles 19 graze over the surface ofthe packaged food product 1 already before the contact with theprotruding edge 4. Upon contact with the edge 4, the bristles 19 exert acompressive force onto it leading to a folding of the edge 4 to liesubstantially flush. While the edge 4 is being pressed against thesurface of the packaged food product 1, the bristles 19 deformelastically and resume their original shape after the food product 1 haspassed the die 5. During the elastic deformation and the subsequentrelaxation or return to the original shape, the bristles cause a springforce which depends on the degree of deformation and acts on the edgeand leads to a folding of the edge to lie substantially flush.

During the passage through the opening 7 of the die 5 in the directionof the arrow R, the bristles graze over the face of the edge facingoutwards after the folding as represented in FIG. 7b . This permits toachieve an over-pressing of the edge, i. e. to realize a change of theangle of the edge by more than 90° relative to the area in which theflanges of the foil half-shells lie one on top of the other, and to foldthe edge to lie substantially flush in particular at surface areas ofthe packaged food product which are not oriented in parallel to themoving direction of the packaged food product through the opening of thedie. Such areas may be convex or concave. Relative to the area in whichthe flanges of the foil half-shells lie one on top of the other, thesesurface areas may be inclined so that they recede from the edge regionof the die while the foil edge is in contact with the edge region and isfolded.

The outer extension of the outer contour of the protruding edge maycomprise concave sections and indentations directed inwards in thecircumferential direction. Thanks to the bristles, the method and devicemay be well adapted to those and other complex circumferential contoursof the edge. The bristles make it easier to deform and fold the edgeeven at indentations or discontinuous extensions at the circumference ofthe edge.

In the represented embodiment, only the bristles of the die come intocontact with the protruding edge. As an alternative, first a rigid partof the die may press onto the edge and the bristles may only be used forthe last step of pressing on the already pre-bent edge. In the sense ofthe invention, a combination of the bristles with a pre-bending element,a multiaxis movement or other already described features is alsopossible.

The material and the geometry of the bristles should be selected suchthat during the edge folding, the bristles will be elastically deformed.The bristles should be sufficiently elastic to exclude a damage of thefood product when the bristles are deformed by the contact and thecompressive forces occurring in the process. Simultaneously, thebristles should be rigid enough to be able to plastically deform theprotruding edge.

To improve the distribution of compressive forces on the surface of thepackaged food product and the edge during folding, or to optimise thefolding quality, the bristles may have different lengths and/ordifferent distances to the surface of the packaged food product.

FIGS. 8a and 8b each show a detail of the packaged food product 1 with aprotruding edge 4 and a die 5 having an elastic element 20 according toan eighth embodiment of the invention. The relative movement of thepackaged food product 1 relative to the die 5 extends in the directionof the arrow R.

The embodiment of the invention represented in FIGS. 8a and 8b differsfrom the variation in FIGS. 7a and 7b in that the edge region of the diehas a rubber lip 21 as elastic element 20. Corresponding referencenumerals are assigned to corresponding features.

The elastic element 20 is designed in the form of a rubber lip 21 in therepresented embodiment of the invention, however, it is not restrictedto this design. The functioning of the elastic element 20 is analogue tothat of the bristles 19. Thus, the elastic element 20 is also suited torealize an over-pressing of the edge 4 by more than 90° and to adapt theedge to surface sections of the packaged food product which are not inparallel to the moving direction of the packaged food product throughthe opening of the die. To this end, the elastic element 20 grazes overthe surface of the packaged food product 1, presses onto the edge 4 tofold it to lie substantially flush, and subsequently grazes over theside of the then folded edge facing outwards.

The elastic element may be made of rubber, silicone, or an elasticpolymer. During the edge folding process, it may be bent over as shownin FIG. 8b . It is also possible that the elastic element is compressedin one or several directions, for example transverse to the movingdirection of the packaged food product. After the contact with thepackaged food product, the elastic element resumes its outer originalshape. The elastic element should have an elasticity which is on the onehand suited to plastically deform the edge, but on the other hand cannotdamage the packaged food product. Similar to the bristles, the elasticelement exerts a spring force onto the foil edge during its deformationwhich acts on the edge.

The elastic element and the bristles may be provided across the entirecircumference of the acting edge region of the die opening, or only inpartial sections of the edge region. Different sections where there maybe elastic elements and/or bristles may alternate with sections of theedge region which are rigid, i. e. act on the edge without any elasticelement or bristles. It is also possible to combine elastic elements,bristles and stiff sections of the edge region so that they act on theedge one after another and thus realize a step-wise folding and pressingon of the edge.

1. Method for folding an edge (4) of half-shells (2) of a foil-likematerial protruding from a surface of the packaging of a packaged foodproduct (1) in which the food product (1) is received to liesubstantially flush, wherein the half-shells (2) comprise flanges (3)lying one on top of the other at least in some sections and forming theprotruding edge (4), characterized in that during a relative movementbetween a die (5) and the package, at least one edge region (8) of theopening (7) of the die (5) presses onto the edge (4) of the foils,whereby the edge (4) of the foils is at least partially folded to liesubstantially flush at at least one half-shell (2).
 2. Method accordingto claim 1, characterized in that at the edge region (8) of the die (5),at least one elastic element presses onto the edge (4) of the foils,whereby the edge (4) of the foils is at least partially folded to liesubstantially flush at at least one half-shell (2).
 3. Method accordingto one of the preceding claims, characterized in that at the edge region(8) of the die, bristles press onto the edge (4) of the foils, wherebythe edge (4) of the foils is at least partially folded to liesubstantially flush at at least one half-shell (2).
 4. Method accordingto one of the preceding claims, characterized in that the die (5) is atrest and the packaged food product (1) is moved relative to the die (5)through the opening (7), or that the packaged food product (1) is atrest and the die (5) is moved relative to the packaged food product (1).5. Method according to one of claims 1 to 3, characterized in that boththe packaged food product (1) and the die (5) are moved.
 6. Methodaccording to one of the preceding claims, characterized in that the edge(4) of the foils is, during the passage through the opening (7) of thedie (5), in a first step initially approached to the surface of thehalf-shells (2), and subsequently, in a further step, folded to liesubstantially flush at at least one half-shell (2).
 7. Method accordingto one of the preceding claims, characterized in that the relativemovement between the die (5) and the packaged food product (1) extendsone-dimensionally.
 8. Method according to one of claims 1 to 6,characterized in that the relative movement of the packaged food product(1) first extends in a first moving direction through the opening (7) ofthe die (5), and subsequently transverse to the first moving directionto adapt the folding of the edge (4) to the outer shape of the foodproduct (1).
 9. Method according to one of the preceding claims,characterized in that the packaged food product (1) is moved relative tothe die (5) with the aid of guide means (6).
 10. Method according toclaim 9, characterized in that the packaged food product (1) is held atthe guide means (6) during the relative movement.
 11. Method accordingto claim 10, characterized in that the packaged food product (1) is heldat the guide means (6) by a vacuum.
 12. Method according to one of claim10 or 11, characterized in that the packaged food product (1) is heldbetween the guide means (6) and a backing part (10).
 13. Methodaccording to claim 12, characterized in that the backing part (10)exerts a guide force onto the packaged food product (1), in particularby means of a resilient element (17).
 14. Method according to one ofclaim 12 or 13, characterized in that at least part of the guide forcebetween the guide means (6) and the backing part (10) is transmitted viathe packaged food product (1).
 15. Method according to one of claims 12to 14, characterized in that the guide means (6) and the backing part(10) are spaced apart so that a folding of the edge (4) non-obstructedby these parts is ensured.
 16. Method according to one of the precedingclaims, characterized in that the protruding edge (4) has a proximalsection (14) which is directly connected to the half-shells (2) andconnects a distal section (15) of the edge with the half-shells (2),wherein the distal section (15) is folded onto the proximal section (14)before the folding of the edge to lie substantially flush.
 17. Methodaccording to claim 16, characterized in that, before the folding to liesubstantially flat, the distal section (15) is directed with its frontend towards the surface of at least one half-shell (2) and in particulartouches it or is spaced apart from it.
 18. Method according to one ofclaim 16 or 17, characterized in that the packaged food product (1)moves, with the proximal section (14) leading, through the opening (7)of the die (5) so that the proximal section (14) comes into contact withthe edge region (8) of the opening (7), and the distal section (15) isat least partially folded to lie substantially flush at at least onehalf-shell (2).
 19. Method according to one of the preceding claims,characterized in that the flanges (3) are bordered and/or sealed to eachother before the folding of the edge (4) to lie substantially flush. 20.Method according to one of the preceding claims, characterized in thatthe packaged food product (1) completely passes through the die (5). 21.Device for folding an edge (4) of a packaged food product (1) to liesubstantially flush, which comprises a die (5) with an opening (7)formed by an edge region (8) of the die (5), a packaged food product (1)which is received between half-shells (2) of a foil-like material (5),wherein the half-shells (2) comprise flanges (3) at least partiallylying one on top of the other and forming an edge (4) protruding fromthe surface of the packaging, and guide means (6) by which the packagedfood product (1) and the opening (7) of the die (5) are movable relativewith respect to each other, characterized in that, during a relativemovement of the packaged food product through the opening of the die(5), the protruding edge (4) can be brought into contact with the edgeregion (8) of the opening so that the protruding edge (4) may be atleast partially folded to lie substantially flush at at least one of thehalf-shells (2).
 22. Device according to claim 21, characterized in thatthe edge region (8) has at least one elastic element pressing onto theprotruding edge (4).
 23. Device according to one of claims 21 and 22,characterized in that the edge region (8) has bristles which press ontothe protruding edge (4).
 24. Device according to one of claims 21 to 23,characterized in that the clearance (A) between the edge of the die (5)bordering the opening (7) and the half-shells (2) is, at least in somesections, smaller than the width (B) of the protruding edge (4). 25.Device according to one of claims 21 to 24, characterized in that theclearance (A) between the edge of the die (5) bordering the opening (7)and the half-shells (2) corresponds, at least in some sections, to thethickness (D) of the protruding edge (4).
 26. Device according to one ofclaims 21 to 25, characterized in that the guide means (6) compriseretention means (11) for the packaged food product (1).
 27. Deviceaccording to claim 26, characterized in that one or several suctionelements are provided as retention means (11).
 28. Device according toone of claims 21 to 25, characterized in that a backing part (10)opposite the guide means (6) is provided with which the packaged foodproduct (1) may be held between the guide means (6) and the backing part(10).
 29. Device according to claim 28, characterized in that thebacking part (10) exerts a compressive force onto the packaged foodproduct (1) which is directed opposite to the direction of the relativemovement of the food product (1) through the opening (7) of the die (5).30. Device according to claim 29, characterized in that the backing part(10) includes a resilient element (17) which may exert a compressiveforce onto the packaged food product (1).
 31. Device according to one ofclaims 21 to 30, characterized in that it furthermore comprises apre-bending element (12) for approaching the edge (4) to the surface,having an opening (7) whose edge region is further spaced apart from thehalf-shells (2) than the thickness (D) of the flanges (3) lying one ontop of the other in some sections.
 32. Device according to one of claims21 to 31, characterized in that the die (5) is fixed and the guide means(6) are movable, or that the guide means (6) are fixed and the die (5)is movable.
 33. Device according to one of claims 21 to 32,characterized in that the die (5) and the guide means (6) are movable.34. Device according to one of claims 21 to 33, characterized in thatthe die (5) and the guide means (6) are movable relative with respect toeach other in one single direction or in several directions.
 35. Deviceaccording to one of claims 21 to 34, characterized in that the edgeregion of the opening of the pre-bending element (12) tapers towards theedge region (8) of the opening (7) of the die (5).
 36. Device accordingto one of claims 21 to 35, characterized in that the pre-bending element(12) is embodied as a chamfer (13) of the edge region (8) of the opening(7).
 37. Device according to one of claims 21 to 36, characterized inthat the flanges (3) at least partially lying one on top of the otherare bordered and/or sealed to each other.
 38. Device according to one ofclaims 21 to 37, characterized in that the guide means (6) and thebacking means (10) are spaced apart.